The present invention relates to an antidecay and antitermite controlling agent for timber, which can preserve timber against decay and at the same time prevent and control termite damage to the timber.
The need of agents for the preservation of timber against decay and those for the prevention and control of termite damage to timber has become pressing with the diversification of timber utilization as well as the change in life style in recent years. For example, under environmental conditions of housing today, timbers used for foundations or the like are deteriorated in a short period of time by wood-rotting fungi represented by Tyromyces palustris, Merulius lacrymans and Coriolus versicolor. Furthermore, the termite damage to housings and trees has been kent increasing for these years; the estimated damage in Japan reaches as much as tens of millions of yen annually. The damage is frequently found in places with high humidity, such as under the floor, and in a kitchen, a bathroom and a lavatory. On the other hand, in such places where the humidity is high, timbers are easily decayed, which in turn makes in turn the timbers susceptible to the damage by termites. Therefore, preservation of timber against decay is effective also in terms of controlling damage by termites; thus antidecay agents and antitermite agents are indispensable as agents for the preservation of timber.
Known examples of agents conventionally used for preservation of timber against decay include organic agents, e.g. phenol compounds, organic halogen compounds, organic tin compounds, naphthenic acid compounds and tar compounds, and inorganic compounds, e.g. Walman salt compounds (a mixture of fluoride compounds, chromic compounds and phenols).
However, the conventional organic agents have disadvantages such that they are strongly toxic to humans and animals and cause irritation and rashes on the skin, and furthermore they have unpleasant order and stain timbers. On the other hand, the inorganic agents have to be used at high concentrations, so that large amounts are needed. Furthermore, some conventional termite-controlling agents exert adverse effects on human and animals; for example, CCA agents contain harmful metals or organic chloride compounds and organic phosphate compounds are strongly toxic.